Clean up Stoplightisms

[philsturgeon]

Here's a list of rules that ended up in spectral:oas because a) I happened to put that into Speccy before they copied it, or b) to help you make your OpenAPI look better in Stoplight.

None of these rules any anything to do with basic OAS validity and as such I would love for them to be removed from any new core OAS package (e.g. openlint:openapi) but of course kept around in some legacy form.

• contact-properties
• info-contact
• info-description
• info-license
• license-url
• openapi-tags-alphabetical
• operation-singular-tag
• operation-tags
• tag-description

Some linters such as Vacuum hide this behind "strict" mode, but what does that mean? It's not strictly more valid, its just stuff I was getting moaned at for adding at WeWork and I wanted to tuck it away behind a Gold Star Good Dog mode to get people onto the Speccy pipeline at all, then ratched up later.

Each of those rules could have a new home in themed rulesets.

1. Documentation - A ruleset that pushes you to leverage OpenAPI nicely for the vast majority of documentation tools. I started this with spectral-documentation, and the following rules could move over there:

• contact-properties
• info-contact
• info-description
• info-license
• license-url
• openapi-tags-alphabetical
• tag-description
• operation-tags

2. No reason for operation-singular-tag that was just a lack of creativity in Stoplight for what to do with multiple tags, and the new OAS 3.2 tags.[].kind keyword resolves that nicely. With multiple kinds of tag people are more likely to use them more, so we should ditch this anyway.